Lack of communication and clarity. Was hired to work as a software engineering consultant for one of their clients. Initially I was told that there were delays in paper work but nothing to worry about, a few weeks later the project had been cancelled but I was told there was the possibility that another project would be started with the same company and they would update me. I never received any updates and messages went unanswered. Additionally, it was not clear during the interview that the project was not finalized and they were still waiting to finalize terms with the client. As far as I could tell, the project was definitely happening until I heard about the delays. One person I know left her job for this one only to have the project be cancelled and to have to scramble to find a new job. I understand that these things can happen in the life of consulting and contracting, but the lack of communication after the initial news as well as the appearance that the project had already been agreed on during interviews is the real red flag here.
Only provide 9 days of PTO. If I remember correctly, that included sick leave.